Infratemporal fosssa and TMJ

Question 1

What is the infratemporal fossa?

Answer 1

space beneath base of the skull and ramus of mandible

Question 2

Boundaries of infratemporal fossa

Answer 2

Anterior : posterior surface of maxilla
Posterior : styloid process
Superior : infratemporal surface of great wing of sphenoid 
Medial: lateral pterygoid plate
Lateral: ramus of mandible

Question 3

Contents of ITF

Answer 3

lateral and medial pterygoid 
Mandicular divison of trigeminal and branches 
pterygoid venous plexus 
chorda tympani 
otic ganglion

Question 4

Maxillary artery

Answer 4

Deep temporal, masseteric and pterygoid branches to muscles

Maxillary artery passes between 2 heads of lateral pterygoid to go into pterygomaxillary fissure - fossa and give off the posterior superior alveolar branch

Question 5

3 parts to maxillary artery passing between pterygoid

Answer 5

mandibular, pterygoid and pterygopalatine

Question 6

Pterygopalatine branches =

Answer 6

Posterior superior alveolar - upper molar and premolar
Infraorbital- canal in floor of orbit, foramen
Anterior superior alveolar- upper incisor and canine

Palatine, pharyngeal and spheonopalatine branches -discuss later

Question 7

Pterygoid venous plexus

Answer 7

surrounds lateral pterygoid
veins form orbit, nasal, and oral cavity
communicates with cavernous sinus and facial veins

Drained maxillary veins
Route for infections

Question 8

TMJ

Answer 8

Temporomandibular Joint

Question 9

What type of joint is the TMJ

Answer 9

synovial joint

Question 10

Where is the TMJ

Answer 10

between the head of the mandible and mandibular fossa and articulate tubercle on the squamous part of the temporal bone

Articular surface fibrocartilage (membranous ossification)
Has a fibrous capsule

Question 11

Nerve supply to TMJ

Answer 11

auriculotemporal and masseteric

Question 12

What reinforces the capsule of TMJ

Answer 12

lateral (temporomandibular) ligament

Question 13

What is medial to TMJ

Answer 13

sphenomandibular and stylomandibular ligaments

Question 14

What attaches to articulate disc and capsule of TMJ

Answer 14

lateral pterygoid

Question 15

What is the cavity of the TMJ divided by?

Answer 15

fibrous articulate disc

Question 16

What does the disc do to the articulate surface

Answer 16

increases congruity of articulate surfaces

Question 17

Head of mandible and disc =

Answer 17

elevation and depression (hinge)

Question 18

Disc and mandibular fossa and articular process =

Answer 18

protrusion and retraction (gliding)

Question 19

To close mouth =

Answer 19

elevation and rectraction (pull condyle backwards

Question 20

To open mouth =

Answer 20

both sides depression and protrusion to slide disc and condyle forwards towards tubercle

Question 21

Asynchronous gliding =

Answer 21

chewing

Question 22

Elevation

Answer 22

head of mandible and disc move backwards and head rotates on lower surface of disc
- temporalis, masseter and medial pterygoid

Question 23

Depression

Answer 23

head of mandible rotates on undersurface of articular disc and mandible is pulled forward
- lateral pterygoid, digastric, geniohyoid, mylohyoid, gravity

Question 24

Protrusion

Answer 24

articular disc and head of mandible moved forward
Movement in upper cavity
- lateral pterygoid (medial pterygoid)

Question 25

Retrusion

Answer 25

articular disc and head of mandible pulled backwards into mandibular fossa
- posterior fibres temporalis

Question 26

Lateral chewing

Answer 26

protrusion and retrusion combined

-pterygoids